Americans are spending more on tricking out the places where they swim. Here's a look at the new wave of accessories

Americans love to overbuild their homes. We put ranges in our kitchens with enough BTUs to light Paris at Christmas, then use them to reheat Domino's. Some even frill up their laundry rooms with stereos and $5,000 mini dry cleaners. So it shouldn't be surprising that rich people are now moving the overdesigning craze outside, to their pools and decks.

Gone are those concrete rectangles plowed into the backyard and surrounded with that plastic patio furniture that sticks to your legs. Instead, homeowners are installing pools with underwater speakers, fire pits--even fake lagoons that emit something the pool industry calls Faux...